package com.lbfamous.genericReflection;

import java.lang.reflect.Method;
import java.lang.reflect.Type;
import java.lang.reflect.*;
import java.util.*;
import java.util.Scanner;


/**
 * GenericReflectionTest
 */
public class GenericReflectionTest {


    public static void main(String[] args) {
        
        String name ;
        if (args.length > 0 ) {            
            name = args[0];
        } else {
            try(Scanner in = new Scanner(System.in)) {
                System.out.println("Enter class name(e.g. java.util.Collections):");
                name = in.next();
            }
        }

        try {
            
            Class<?> cl = Class.forName(name);
            //print("")
            printClass(cl);

            for (Method m : cl.getDeclaredMethods()) {
                printMethod(m);
            }            
        } catch (ClassNotFoundException e) {
            //TODO: handle exception
            e.printStackTrace();
        }
    }

    public static void printClass(Class<?> cl) {
        
        System.out.print(cl);
        printTypes(cl.getTypeParameters(), "<", ", ", ">",true);

        Type sc = cl.getGenericSuperclass();
        if (sc != null) {
            System.out.print(" extends ");
            printType(sc, false);
        }
        printTypes(cl.getGenericInterfaces(), "implements ", ", ", "", false);

        System.out.println();
    }


    public static void printMethod(Method m) {
        
        String name = m.getName();
        System.out.print(Modifier.toString(m.getModifiers()));
        System.out.print(" ");
        printTypes(m.getTypeParameters(), "<", ", ", ">", true);

        printType(m.getGenericReturnType(), false);
        System.out.print(" ");
        System.out.print(name);
        System.out.print("(");

        printTypes(m.getGenericParameterTypes(), "", ", ", "", false);
        System.out.println(")");

    }

    public static void printTypes(Type[] types,String pre,String sep,String suf,boolean isDefinition) {
        
        if(pre.equals(" extends ") && Arrays.equals(types, new Type[]{Object.class}))
            return;
        
        if(types.length > 0)
            System.out.print(pre);
        
        for (int i = 0; i < types.length; i++) {
            if(i > 0)
                System.out.print(sep);
            printType(types[i], isDefinition);
        }

        if(types.length > 0)
            System.out.print(suf);
    }

    public static void printType(Type type,boolean isDefinition) {
        
        if (type instanceof Class) {
            Class<?> t = (Class<?>)type;
            System.out.print(t.getName());
        }else if(type instanceof TypeVariable) {

            TypeVariable<?> t = (TypeVariable<?>)type;
            System.out.print(t.getName());
            if(isDefinition){
                printTypes(t.getBounds(), " extends ", " & ", "", false);
            }
        }else if(type instanceof WildcardType){

            WildcardType t = (WildcardType)type;
            System.out.print("?");
            printTypes(t.getUpperBounds(), " extends ", " & ", "", false);
            printTypes(t.getLowerBounds(), " super ", " & ","",false);
        }else if (type instanceof ParameterizedType){
            ParameterizedType t = (ParameterizedType)type;
            Type owner = t.getOwnerType();
            if(owner != null){
                printType(owner, false);
                System.out.print(".");
            }
            printType(t.getRawType(), false);
            printTypes(t.getActualTypeArguments(),"<",", ",">",false);
        }else if(type instanceof GenericArrayType){

            GenericArrayType t = (GenericArrayType) type;
            System.out.print("");
            printType(t.getGenericComponentType(), isDefinition);
            System.out.print("[]");
        }
    }
}